In 90% cases All four 3rd molar  dont there specific dirction of erruption.they errup in any direction,due to that many pbls created-

1-Accumulation off food which pain and swalling and in sevear case cause loss of opning mouth

2-when it is tillted to towed adjecent tooth it causes careies

3-While irregularly irrupting it give pressure to adjecent tooth and make occlusion disturb.

Precautions-  

Go for extraction or if it will coorected by ortho treatment then go for that.